American Petroleum Institute (API) Chapter 11.1 Equations

Flow-Cal, Inc. and the American Petroleum Institute (API) – Chapter 11.1 provides the algorithm and implementation procedure for the correction of temperature and pressure effects on density and volume of liquid hydrocarbons.

API Chapter 11.1 Volume Correction Factors

The American Petroleum Institute has joined forces with Flow-Cal, Inc. to develop, market, and support the API Chapter 11.1 code (Temperature and Pressure Volume Correction Factors for Generalized Crude Oils, Refined Products, Special Applications, and Lubricating Oils). This information is available in equations relating volume to pressure, which contains physical data that has direct application to volumetric measurement of liquid hydrocarbons.

Physical Properties Data

The subroutines for all the volumes of API Chapter 11.1 are now available in electronic form. This document contains the source code in C computer language to generate the various Volume Correction Factor tables. The source code may require modification for some computer systems to conform to the file naming convention of the computer system being used. This standard provides the algorithm and implementation procedure for the correction of temperature and pressure effects on density and volume of liquid hydrocarbons, which fall within the categories of crude oil, refined products, lubricating oils, and special applications.

Microsoft Excel® Add-in Program

The Excel Add-in function is a PC based spreadsheet for Microsoft Excel used to perform net corrected volume calculations for virtually all petroleum custody transfer and inventory control procedures. Users will be able to print customized VCF tables for API Gravity, density, and temperature.

For those that prefer a quick look-up guide over an electronic version, printed temperature correction (CTL) tables of the API Chapter 11.1 – 2004 algorithms are also available. The VCF manuals are offered in an abridged version, providing the optimal table range, or the full version with the complete table range. Custom ranges are available upon request.

The complete library of VCF manuals is listed below in both the U.S. Customary and SI Series.

To purchase these tables or request additional information, please Contact Us or phone (281) 282-0865 to speak to our sales staff. A minimum order of 10 books is required for purchase.

U.S. Customary Series

API GravityVolumes 1-8

Relative DensityVolumes 9-16

Volumes 1-8 are published for a temperature base of 60 Degree Fahrenheit, with API gravity and Degree Fahrenheit units as the lookup reference (using 0.5° gravity and 0.1° temperature increments). The abridged version is approximately 400 pages that include the following ranges: 15.0 – 89.9°API and 10.0 – 113.9°F.

Volumes 9-16 are published for a temperature base of 60 Degree Fahrenheit, with Relative Density and Degree Fahrenheit units as the lookup reference (using 0.002 relative density and 0.1° temperature increments). The abridged version is approximately 400 pages that include the following ranges: 0.6390 – 0.9370 Relative Density and 10.0 – 113.9°F.

Volume 1: 11.1.6.2 (Table 5A) Generalized Crude Oils

Volume 9: 11.1.6.2 (Table 23A) Generalized Crude Oils

Volume 2: 11.1.6.1 (Table 6A) Generalized Crude Oils

Volume 10: 11.1.6.1 (Table 24A) Generalized Crude Oils

Volume 3: 11.1.6.2 (Table 5B) Refined Products

Volume 11: 11.1.6.2 (Table 23B) Refined Products

Volume 4: 11.1.6.1 (Table 6B) Refined Products

Volume 12: 11.1.6.1 (Table 24B) Refined Products

Volume 5: 11.1.6.2 (Table 5C) Special Applications

Volume 13: 11.1.6.2 (Table 23C) Special Applications

Volume 6: 11.1.6.1 (Table 6C) Special Applications

Volume 14: 11.1.6.1 (Table 24C) Special Applications

Volume 7: 11.1.6.2 (Table 5D) Lubrication Oils

Volume 15: 11.1.6.2 (Table 23D) Lubrication Oils

Volume 8: 11.1.6.1 (Table 6D) Lubrication Oils

Volume 16: 11.1.6.1 (Table 24D) Lubrication Oils

SI Series

Kilogram per Cubic Meter at 15°CVolumes 17-24

Kilogram per Cubic Meter at 20°CVolumes 25-32

Volumes 17-24 are published for a temperature base of 15 Degree Celsius, with density using Kilogram per Cubic Meters and Degree Celsius units as the lookup reference (using 2.0 kg/m3 and 0.05° temperature increments). The abridged version is approximately 450 pages that include the following ranges: 638.0 – 936.0 kg/m3 and -12.0 – 46.45°C.

Volumes 25-32 are published for a temperature base of 20 Degree Celsius, with density using Kilogram per Cubic Meters and Degree Celsius units as the lookup reference (using 2.0 kg/m3 and 0.05° temperature increments). The abridged version is approximately 450 pages that include the following ranges: 638.0 – 936.0 kg/m3 and -12.0 – 46.45°C.